ATmega3290P datasheet(220/385 Pages) ATMEL

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8021E–AVR–07/09

ATmega329P/3290P

• Differential Non-linearity (DNL): The maximum deviation of the actual code width (the interval

between two adjacent transitions) from the ideal code width (1 LSB). Ideal value: 0 LSB.

Figure 21-13. Differential Non-linearity (DNL)

• Quantization Error: Due to the quantization of the input voltage into a finite number of codes, a

range of input voltages (1 LSB wide) will code to the same value. Always ± 0.5 LSB.

• Absolute Accuracy: The maximum deviation of an actual (unadjusted) transition compared to

an ideal transition for any code. This is the compound effect of offset, gain error, differential

error, non-linearity, and quantization error. Ideal value: ± 0.5 LSB.

21.8

ADC Conversion Result

After the conversion is complete (ADIF is high), the conversion result can be found in the ADC

Result Registers (ADCL, ADCH).

For single ended conversion, the result is

where V

IN is the voltage on the selected input pin and VREF the selected voltage reference (see

Table 3 on page 222 and Table 21-3 on page 223). 0x000 represents analog ground, and 0x3FF

represents the selected reference voltage minus one LSB.

Output Code

0x3FF

0x000

VREF Input Voltage

DNL

1 LSB

ADC

VIN 1024

⋅

VREF

--------------------------

ADC

VPOS VNEG

–

() 512

⋅

VREF

-----------------------------------------------------

ATmega3290P Datasheet(PDF) 220 Page - ATMEL Corporation